Video noise reduction filters have been extensively used in both post-production and video compression environments. The former often require filters which preserve as much detail as possible, and therefore tend to use very conservative settings which may lead to uneven noise removal over the picture. The latter often require high filtering strength, even at the expense of some loss in detail, because the goal is to reduce the amount of information in the video and thereby increase compression efficiency (that is, reduce bit rate). Various applications seek to achieve a balance between uneven noise removal and loss in detail.